The invention is related to providing an electronic wave heating apparatus using the ultrahigh frequency of the electronic wave (referred to the microwave below) generated by a magnetron, and particularly to providing a structure of an electronic wave heating apparatus for preventing the leakage of the microwave.
It has been known that a heating apparatus using the microwave frequency of the magnetron has not been attempted in the prior art until now.
The heating apparatus is generally referred as to a heating apparatus for heating a room in order of the heating of the indoor air and the convection of the heated air. The type of a heating apparatus is at most classified by a heat source. In other words, current heating apparatus use the heat energy generated according to the combustion of fuel or the application of a power source to the electric coil or the nichrome wire.
Even though a relatively superior heating apparatus for the firing of fuel, for example gas or petroleum, is used to heat a room, the fact is that complete combustion has not yet been realized in spite of their research and development. Thus when the fuel is burnt, it has a problem that a heating apparatus causes smoke pollution having the incomplete combustion gas. In order to reduce the smoke pollution, a heating apparatus tends to be complex and is made relatively large, following that it is not economical in light of its manufacturing cost.
Further, a conventional heating apparatus could not avoid generation of soot or poisonous gas harmful to the human body, if it is used for a long period. It has had the inconvenience and problems that the indoor air must be exchanged with the fresh air to prevent a loss of life during its use in the closed space.
Also, a conventional heating apparatus using the power source is provided with an electric coil, such as nichrome wire, which is in the form of a concentric circle, and a thermal reflecting plate mounted around or near its periphery, so that when the power source is applied the heat energy generated from the electric coil is reflected by means of the thermal reflecting plate to heat the air. But it has happened often that a fire accident has been caused by overheating of the electric wire or a safety accident by a short circuit.
Also, such like heating apparatus could not meet the user's expectation with respect to the heating effect and the heating time taken since their initial heating is weak and/or their uniform indoor heating takes relatively longer.
In light of these points, it is very innovative that the heating effect is maximized as well as ideal indoor heating is realized without smoke pollution caused by incomplete combustion gas, or the problems of the fire and safety accidents.
On the other hand, it is well known that a microwave oven using the microwave generated from the magnetron performs a cooking operation with a dielectric heating plate or a absorbing plate which absorbs the energy generated by the microwave and emits heat. Therefore, assuming that a microwave oven is used as a heating apparatus without the leakage of microwaves, it is noted that the disadvantages of the conventional heating apparatus can be easily overcome.
That is to say, a conventional typical microwave oven is described in Japan Patent Publication No. Sho. 51-10689. Japan Patent Publication No. Sho. 51-10689 discloses that the microwave energy generated by the magnetron is introduced into the lower portion of the heating room through the waveguide, and the microwave absorbant for absorbing the microwave energy is mounted on the lower portion of the heating room to emit heat, thereby cooking the foods placed on the lower portion.
With it, a microwave oven can be adapted to a heating apparatus on the ground of the fact that it must be provided with means for blowing the heat-exchanged air into the indoor, means for introducing/discharging the air, and means for preventing the leakage of microwaves.